Watercraft that incorporate foam with the hull of a watercraft are known in the art, for example, in U.S. Pat. No. 4,060,865, to Woolworth. Typically, foam is incorporated and enclosed within the hull structure itself. These boat designs are generally safer than designs that do not incorporate flotation devices within the hull. Outboard flotation members mounted to the sides of a boat are also known in the art. For example, in U.S. Pat. No. 4,287,624, to Lowther, foam flotation devices are attached to the exterior and interior of a low-speed fishing boat.
In U.S. Pat. No. 5,282,436, to Hansen, the present inventor discloses outboard foam stabilizing members suitable for use on high-performance watercraft. Hansen discloses a watercraft having a rigid, planing hull and exterior foam stabilizing members that extend substantially around the perimeter of the boat hull. The foam stabilizing members are configured to remain substantially out of contact with the surface of the water when the boat is at cruising speed, so that the foam stabilizing members do not contribute to the wetted surface area of the watercraft while planing. The foam stabilizing members also act as a running surface when a sharp turn is performed at high speed.
In U.S. Pat. No. 6,810,827, to Hansen, a watercraft with an outboard stabilizing member (or collar) that combines inflatable inboard and outboard air bladders with a foam member disposed between the inboard and outboard bladders is disclosed. Other stabilizing collars that combine air bladders and foam members are disclosed in U.S. Pat. No. 7,201,865, to Hansen, and in U.S. Pat. No. 6,371,040, to Hemphill et al.
In some embodiments the outboard stabilizers extend from the side sheets along substantially the entire length of the watercraft, from bow to stern. Alternatively, outboard stabilizers may extend along only a portion of the vessel side sheets. The outboard stabilizers must be securely fixed to the watercraft because outboard stabilizers are subject to very significant hydrodynamic forces, especially on high-performance watercraft. It is important for the integrity of the vessel that outboard stabilizers be fastened securely to the watercraft.
Outboard stabilizing members that combine air bladders and foam members have become popular because they provide advantages over prior art air-only or foam-only stabilizing members. For example, air-only stabilizing members may become entirely ineffective if they are punctured due to loss of air. Foam-only stabilizing members, on the other hand, are typically difficult to remove. Removal of the stabilizers for conventional watercraft may be desirable, for example, to facilitate trailering or otherwise transporting the watercraft. Typically the air bladders and/or foam members are enclosed in a collar or sheath for attachment to the watercraft.
However, a disadvantage of conventional outboard stabilizing members that combine air bladders and foam members is that the foam members are compressed by the air bladders. The polymeric foams used for stabilizing members will shrink or compress when an external compressive force is applied. In fact, this property of the foam is often utilized to facilitate assembly of the stabilizing members. However, compression of the foam members during use may cause the foam members to become loose in the stabilizing member assembly. In order to compensate for the smaller foam members, a user may inflate the bladder(s) further, thereby reapplying a compressive force on the foam member and causing the foam member to shrink further. Compressive shrinking of the foam may cause the collar to take on an undesirable shape and/or interfere with the attachment mechanism for the stabilizing members. In particular, the compressed foam members will provide less buoyancy.
This could be catastrophic, in particular if the air bladders are punctured, for example, in an accident event in which the foam members are relied on to keep the vessel afloat. The polymeric foam member may retain its compressed shape and volume for hours after the compressive force has been removed. Therefore, in an accident scenario wherein the air bladder has overly compressed the foam member and then deflated in a catastrophic event, the smaller compressed foam member will not provide the buoyancy that it was designed to provide.
One challenge that has limited broader adoption of outboard stabilizers for high-performance watercraft is the additional maximum width, or beam, that results from outboard stabilizers. Watercraft may often be towed or otherwise transported over highways to a desired launch site. Highways generally have limitations on allowable vehicle width. For example, in the United States federal law sets a maximum commercial vehicle width of about 102 inches on the national network of highways (without special over-width permits) in 23 CFR Part 658.
In order to increase the usable interior space of a towable watercraft having outboard stabilizers, it would be beneficial if the outboard stabilizers could be decreased in size or easily removed for transporting or towing the vessel, and easily and quickly reinstalled or expanded when the vessel arrives at the desired launching location. Prior art attachment mechanisms for outboard stabilizers typically require many hours and trained personnel to remove and reinstall. Such removal and installation may also require special tools and the like. There is a need for improved methods and systems for attaching outboard stabilizers to watercraft.
There is also a need for an air/foam stabilizing member that can be repaired in situ. It would be beneficial to provide a stabilizing member with separable air bladders that can be quickly removed, repaired, and replaced without removing the buoyant stabilizing member from the watercraft, such that the foam members' contribution to the buoyancy of the stabilizing member is retained during the repair or maintenance.